JPS62180762A - Manufacture of ball for treating powdered body - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] <Industrial Application Field> The present invention relates to a powder processing ball' (hereinafter simply referred to as a ball).
0 regarding the manufacturing method of ・Crushing and mixing the object,
Various powder processing devices are used for dispersing, crushing, and even drying.

This type of powder processing equipment □fills the object into a container,
When the container is subjected to rotation, vibration, etc., the object is processed according to the purpose, but at this time, balls are generally loaded as a processing medium inside the container to improve powder processing efficiency. There's a lot going on.

By the way, in the recent era of high-level technological products, it is required that powder processing equipment be able to obtain highly purified processed materials. For example, in the electronics field, semiconductors, piezoelectric elements, IC circuits, etc. are manufactured in large quantities.
(Many of these products use high-purity ceramic moldings. These high-purity ceramic moldings are generally made using finely ground high-purity ceramic powder.
Additives are added, mixed or dispersed, molded into the desired shape, and then fired.Due to the nature of the high-purity ceramic powder that is the raw material, care is taken to ensure that the performance of each product is not adversely affected. Therefore, it is required that the amount of inorganic impurities that are not removed by firing in each of the product manufacturing steps is as low as possible.

On the other hand, when an object is processed by a powder processing apparatus, one of the main causes of inorganic impurities being mixed into the object is the balls used during powder processing.

This is because the balls are generally made of metal in relation to powder processing efficiency, but the balls collide violently with each other or between the balls and the container during powder processing. This is because the outer circumferential surface of the ball is subject to impact drop, wear, etc.

The present invention relates to a method for producing a ball that meets the recent demand that the processed material must be of high purity while taking into consideration powder processing efficiency, and in particular, a method for producing a ball whose core metal ball is coated with a synthetic resin. It is something.

<Prior art, its problems, etc.> Conventionally, a ball itself in which the outer peripheral surface of a metal ball is coated with synthetic resin has been proposed (Japanese Patent Publication No. 46-25226,
Special Publication Showa 49-21401. JP-A-55-84547).

However, these conventional proposals do not disclose a method for manufacturing such a ball. What is important in manufacturing such balls is that the metal ball is positioned at the center of the ball as a whole, and that the ball can be manufactured efficiently, as well as the durability of the ball. If the metal ball, which has a decisive influence on the center of gravity of the ball, is not positioned at the center of the ball, the ball will become so-called one-handed during powder processing, and the powder processing will be difficult. Needless to say, this will have an adverse effect on the ball itself, and the durability of the ball will also be significantly reduced.

<Problems to be Solved by the Invention and Means for Solving the Problems> The present invention provides a method for efficiently manufacturing a ball in which a metal ball is positioned at the center and the outer peripheral surface of the metal ball is equally coated with synthetic resin. However, the present invention has the following features:
A synthetic resin receiver is prepared, in which a leg piece is integrally attached to the lower part of the outer periphery of a hollow, approximately semicircular spherical piece, and a tongue piece is integrally attached to the outer periphery side, and the leg piece is fixed to the mold. By bringing the tongue pieces into contact with the inner periphery of the mold, the metal ball placed on the semicircular soil is positioned at the center of the mold whose inner periphery forms a spherical surface. The present invention relates to a method for manufacturing a powder processing ball, which comprises injecting heated and molten synthetic resin into a ball, followed by cooling and surface shaping.

Hereinafter, the configuration of the present invention will be explained in more detail based on Figure (2).

FIG. 1 is a longitudinal sectional view illustrating a receiver used in the present invention, and FIG. 2 is a front view thereof. The receiver 1.1 has a hollow, substantially semicircular spherical piece 12 with a leg piece 13 integrally suspended from the lower center of the outer periphery, and a total of four tongue pieces 12a-12 on the upper end of the outer periphery side.
d (the tongue piece 12d is not shown) is integrally attached and is made of synthetic resin, so the foot piece 13 is divided into an upper part 14 and a lower part 15, and the upper part 14 has a total of four strips along the foot piece 13. Pieces 14a to 14d (strip 14d is not shown) are provided protrudingly. □Figure 3 is a vertical cross section illustrating the state in which the metal ball is positioned at the center of the mold and the synthetic resin is injected in the present invention. It is a diagram. The second mold consists of an upper mold 22 and a lower mold 23. The upper mold 22 has an injection port 22a, and the lower mold 23 has a sinkhole 23a in the center, and both molds are closed. The inner periphery of the mold appears to form a spherical surface as a whole. Open the upper mold 22 and press fit the lower part 15 of the leg piece 13 hanging down from the receiver 11 into the sinkhole 23a of the lower mold 23 to remove the leg piece 13.
to be fixed. The metal ball 31 is placed on the semicircular spherical piece 12 of the receiver 11 at any stage before or after such fixing.

It is preferable that the semicircular spherical piece 12 is larger than half of a circular sphere and its inner diameter is slightly smaller than the outer circumferential diameter of the metal ball 31. In this case, the metal ball 31 is fitted into the semicircular spherical piece 12 as if it were mounted. It becomes a state where

In this case, tongue pieces 12a to 12d (tongue pieces 12b, 12d
(not shown) come into contact with the inner periphery of the upper mold 31 when it is closed, and the metal balls 31. is a mutual relationship in which the inner periphery is positioned at the center of the mold 21 forming a spherical surface. Needless to say, the size of the hemispherical piece 12 and the tongue piece 12a-12
In relation to the attachment position of d, the tongue pieces 12a to 12d are located at the bottom 2
It may come into contact with the inner periphery of No. 3. These tongue pieces 12a to 12d are used to lower the lower part 13 of the leg piece 13 when injecting heated and melted synthetic resin 41 into the mold 21 as described later, depending on the injection pressure, injection time, etc. This effectively prevents the horizontal vibration of the receptor 11 that may occur when the metal ball is simply press-fitted into the sinkhole 23a of the mold 23, and prevents the metal ball from being placed on the receptor 11 due to the horizontal vibration of the receptor 11. 31 is mold 2
This effectively prevents deviation from the center of 1. After closing the upper mold 31, heat and melt the synthetic resin 41 as specified in the mold 2.
The synthetic resin 41 is injected into the interior of the metal ball 11 and cooled to coat the outer circumferential surface of the metal ball 31 held by the receiver 11 with the synthetic resin 41 as it is. In the drawings, the air venting and cooling of the mold 21, as well as the injection device and the like are omitted; however, these steps, including, for example, the application of a mold release agent, may be carried out in accordance with conventionally known injection molding methods.

FIG. 4 is a longitudinal sectional view illustrating a ball manufactured according to the present invention. After cooling according to the procedure described above, the upper mold 21
When the injection molded product is opened and taken out, the part corresponding to the injection port 22a and the joint part between the upper mold 22 and the lower mold 23 are not smooth, and the lower part 15 of the leg piece 13 protrudes. Therefore, the surface of the receiver 13 (the lower part 15 of the leg 14 of the receiver 13) is shaped using a stone or cutter.
The metal ball 31 held by the metal ball 31 (which has been removed) is positioned at the center, and a synthetic resin 41 is placed equally around the outer periphery of the metal ball 31.
(12, 12a-12d, 14) coated balls are produced.

In the present invention, the synthetic resin forming the receiver and the synthetic resin covering the metal ball may be made of the same material or different materials, and there is no particular restriction on these materials, but as desired. In order to facilitate the injection molding of the ball and to ensure sufficient durability of the manufactured ball, the synthetic resin that forms the receiver is made of 6-nylon, and the synthetic resin that covers the metal ball is made of 6.6-nylon. It is better to In order to strengthen the adhesion with the synthetic resin covering the metal sphere, the surface of the metal sphere has been roughened by physical or chemical means, and the outer surface of the metal sphere has been roughened with multiple layers. It is preferable to have a small protrusion or, conversely, a plurality of small depressions on the outer circumferential surface.The material of the metal ball has a high processing efficiency when powder processing is performed using the manufactured ball. In order to improve the

<Example> A ball was manufactured under the following conditions according to the procedure shown in FIGS. 1 to 4 described above.

Receiver: 6-nylon (synthetic resin covering a total of 4 metal balls with tongue pieces (heated and melted and injected)...
6.6-Nylon metal ball -O Lead ball with a diameter of 10 me, outer surface lightly sandblasted Diameter of the spherical surface that forms the inner surface of the mold φ・-24*I Injection molding φ fist・Heating melting temperature of synthetic resin 265-285
℃, injection pressure 50 Kg/cm2, injection time 40 seconds, and cooling time 100 seconds. The upper mold was opened, the injection molded product was taken out, and the surface was shaped with a cutter and sandpaper to produce a desired ball.

<Effects of the Invention> As explained above, the present invention has the effect of being able to efficiently manufacture a ball in which a metal ball is positioned at the center and whose outer peripheral surface is equally coated with synthetic resin. .

[Brief explanation of drawings]

Fig. 1 is a vertical cross-sectional view illustrating the receiver used in the present invention, Fig. 2 is a front view thereof, and Fig. 3 is a diagram showing the injection of synthetic resin by positioning a metal ball to the center of the mold in the wooden invention. FIG. 4 is a vertical cross-sectional view illustrating a ball manufactured according to the present invention. 11--Skewer receiver, 12--Semicircular sphere piece, 12a ~ 12
c * e * Tongue piece, 13... φ foot piece, 21... Mold,

Claims (1)

[Scope of Claims] 1. Prepare a synthetic resin receiver in which a leg piece is integrally attached to the lower part of the outer periphery of a hollow substantially hemispherical piece and a tongue piece is integrally attached to the outer periphery side, and By fixing the piece to the mold and bringing the tongue piece into contact with the inner periphery of the mold, the metal ball placed on the semicircular spherical piece is positioned at the center of the mold, the inner periphery of which forms a spherical surface. A method for manufacturing a powder processing ball, which comprises: injecting heated and molten synthetic resin into the mold, followed by cooling and surface shaping. 2. The method for manufacturing a powder processing ball according to claim 1, wherein the receiver is made of 6-nylon. 3. The method for producing a powder processing ball according to claim 1 or 2, wherein the heated and melted synthetic resin is 6,6-nylon. 4. A method for manufacturing a powder processing ball according to any one of claims 1 to 3, wherein the metal ball has been subjected to surface roughening treatment. 5. The method for manufacturing a powder processing ball according to any one of claims 1 to 4, wherein the metal ball is made of lead.